This invention relates generally to ovens, and more particularly to exhaust ventilation grilles for range applications.
Conventional ovens are either, for example, microwave or radiant cooking type ovens. A microwave oven includes a magnetron for generating RF energy used to cook food in the oven cooking cavity, and radiant cooking ovens include an energy source such as lamps which generate light energy used to cook the food. Although microwave ovens cook food more quickly than radiant ovens, microwave ovens do not brown the food. Radiant ovens brown the food and generally can be used to cook a wider variety of foods than microwave ovens. Therefore, combination ovens have been developed that include both radiant and microwave heating elements to cook a wider variety of foods more quickly.
An oven ventilation system is required for intake of room air into the cooking cavity for cooking operations, and/or for cooling of radiant cooking units, and re-circulation of air back into the room. In some types of ovens, air intake and exhaust is accomplished through ventilation grilles attached to an outer shell of the oven. Due to its low cost and manufacturing versatility, plastic has become a material of choice for oven grilles, and in some cases is used to form decorative grilles on a front face of the oven that add to the aesthetic appeal of the oven.
However, it has been observed that high exhaust temperatures, which may reach 275.degree. F. (135.degree. C.) or greater in a combination oven, and/or grease deposits from cooking cavity exhaust air, adversely affect known plastic grilles of ovens. Resultant grease stains and discoloration of the plastic grilles is highly undesirable. While known plastics exist that maintain grease resistance at elevated temperatures these materials are unacceptable in other aspects, such as UV color stability.
Accordingly, it would be desirable to provide a grease resistant, color stable, plastic oven grille that may withstand severe conditions when used on an oven.